Keith Urban's "Drop Top" is a bass-heavy, EDM-inspired pop-country song, and a singer few people have heard of shares vocals with the superstar. How did Kassi Ashton end up on Urban's Graffiti U album?

Like the other two female artists on the album (Lindsay Ell and Julia Michaels), it happened quite organically, Urban tells the Taste of Country Nights radio show. Pop writer Mozella (Miley Cyrus, "Wrecking Ball") helped write the song, and it became a duet during the writing sessions. So they set out in search of the perfect girl.

"I said, Whoever the girl is she's gotta have the right voice, she's gotta have the right attitude, she's gotta have swagger,'" Urban recalls. "Legit, not faux swagger. The real deal."

Someone told him he needed to meet Ashton, a 24-year-old newcomer from California, Mo., with a streaming single called "California, Missouri." She is now signed to UMG Nashville. Urban and the other writers of "Drop Top" (Jimmy Robbins and Josh Osborne) quickly came to consensus that she was it, and as of Friday (April 27), Urban's fans will be able to hear her at the front of every chorus.

"She reminds me of Kassi Ashton," Urban says when asked how to describe her sound. "She's such a unique, original creature. I don't know who her influences are, but they sound somewhere between Tammy Wynette and Beyonce. It's so extraordinarily unique."

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The song "Drop Top" is about a group of girlfriends taking a road trip to Coachella in a Jeep convertible. That's Urban playing bass guitar — he says he wrote the song on bass, as he often does, because he finds that doing so liberates the melody.

This song is hardly the only one on Graffiti U to whole-heartedly embrace pop music. Ed Sheeran helped write "Parallel Line," a song that also samples a Coldplay song. Michaels helped write several songs on the album, and writer and producer Oscar Holt (Taylor Swift, Hailee Steinfeld, Katy Perry) was a primary contributor to "Way Too Long."

Taste of Country Nights is a syndicated night show which airs on more than 100 radio stations nationwide. Listen to highlights on iTunes or your Android device.

Listen to Keith Urban's Interview With Taste of Country Nights:

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